INVESTIGATION OF CALCIUM CARBIDE RESIDUE AS A STABILIZER FOR TROPICAL SAND USED AS PAVEMENT MATERIAL

Abstract

Wastes that have cementitious properties can become a useful source of cheap materials for soil improvement, thereby reducing the cost of construction projects on sites that have unsuitable soils. This research work investigated the effects of the application of calcium carbide residue (CCR) to a tropical soil on its geotechnical properties in order to assess the suitability of the stabilized soil for use as a road pavement material. Tests to determine the grain size distribution, specific gravity, liquid and plastic limits, compaction, California bearing ratio (CBR) and unconfined compressive strength (UCS) of the natural soil and its stabilization with varying percentages of CCR were carried out. The outcome showed that increasing application of CCR generally reduced the soil’s specific gravity, plasticity index and maximum dry unit weight. A direct proportionality was also found between the CCR content and each of the liquid and plastic limits, optimum moisture content, CBR and UCS. Thus, the soil became more workable and its strength properties were improved by stabilization with CCR. Consequently, the subgrade characteristics of the soil for use as earthwork materials for road construction was improved. Based on strength properties of the stabilized soil, an optimal application of 4% CCR was found suitable for the stabilization of the sand with similar properties as those studied. The use of CCR as for stabilizing sand for road construction is recommended as a cheap and sustainable approach for developing countries.